circumflex, n. [L. circumflexus a bending round, fr. circumflectere, circumflexum, to bend or turn about; circum + flectere to bend. See Flexible.].

A wave of the voice embracing both a rise and fall or a fall and a rise on the same a syllable. Walker. [1913 Webster]
A character, or accent, denoting in Greek a rise and of the voice on the same long syllable, marked thus [~ or Accent, n., 2. [1913 Webster]

circumflex, v. t.

To mark or pronounce with a circumflex. Walker. [1913 Webster]

circumflex, a. [Cf. L. circumflexus, p. p.].

Moving or turning round; circuitous. Swift. [1913 Webster]
Curved circularly; -- applied to several arteries of the hip and thigh, to arteries, veins, and a nerve of the shoulder, and to other parts. [1913 Webster]

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OXFORD DICTIONARY

circumflex, n. & adj.
--n. (in full circumflex accent) a mark. placed over a vowel in some languages to indicate a contraction, length, or a special quality.
--adj. Anat. curved, bending round something else (circumflex nerve).

Etymology

L circumflexus (as CIRCUM-, flectere flex- bend), transl. of Gk perispomenos drawn around

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